Deafness is the most prevalent sensory issue among school children in the United States. Although it has been extensively studied, researchers are just starting to uncover the impact of sound and language on the learning growth of deaf children. Recent studies presented at the American Association for the Advancement of Science shed light on how deafness interacts with other challenges, such as autism, and problems with language and executive function.
Richard Meier, a linguistics and psychology professor at the University of Texas at Austin, emphasized the importance of researching developmental disorders in signing children. By studying deaf students, researchers can gain insights into other cognitive issues, such as autism spectrum disorders. Previous studies have shown that students with autism tend to use names instead of pronouns like "you" or "me" when identifying pictures of themselves or researchers. A similar pattern was observed in deaf students with autism, even when the names were difficult to finger-spell.
In the United States, over 1 in 500 children are born deaf or hard of hearing, making it the most common congenital sensory problem. These children also have higher rates of neurological issues, including autism. However, only about 1 in 4 children with hearing loss are properly diagnosed and receive services before the age of 6 months, despite the fact that 98 percent of newborns undergo a hearing test.
The experiences of deaf children in their first six months of life vary greatly. Depending on whether they are born to hearing parents or deaf parents who use sign language, their language development can differ significantly. Approximately 5 percent of deaf children are born to deaf parents and are exposed to sign language from birth. These children typically reach language milestones at similar ages to hearing children. However, the majority of deaf babies (9 in 10) are born to hearing parents who may take months or years to learn sign language fluently, if they do at all. This lack of early language exposure can have long-term effects on attention and self-control in children with hearing problems.
Language deprivation, rather than auditory deprivation, is the primary factor contributing to executive function problems in deaf children, according to research by Matthew Hall and Peter Hauser. To illustrate this, a study found that kindergarten teachers had to gesture twice as often to gain the attention of children who had not been exposed to significant sign language before age 3, compared to those who had been signing since birth. Another study by Hauser tested deaf children’s executive function skills and found that those who had learned to sign before age 3 performed significantly better than those who started signing later. Similarly, a study on deaf children with cochlear implants showed that those who were fluent in American Sign Language performed on par with hearing children, while those who received the implant but no sign language performed worse.
In conclusion, further research on the language and cognitive development of deaf children is essential for both practical and scientific reasons. It allows researchers to understand the similarities and differences between typically developing children and those with developmental disorders who use sign language. This knowledge can inform interventions and support systems to improve the learning and overall well-being of deaf children.
“The significance of early language and instruction for parents and classrooms is immense," stated Hauser. This statement may be met with controversy, as some researchers argue that deaf children who receive cochlear implants should only be provided with spoken interventions. However, a recent study published in the journal Pediatrics, which examined over 400 studies conducted over a period of 20 years, compared different interventions for deaf children. Only a few studies compared the use of sign language with oral language for children who had hearing deficits before the age of 3, and the quality of these studies varied greatly.
The use of sign language can also benefit educators and researchers in understanding children who are not developing typically. For instance, researchers studying autism, such as Aaron Shield, a speech-language pathologist at Miami University of Ohio, have long debated why children with autism often have difficulty using pronouns. In previous studies, hearing children with autism tended to refer to specific names instead of using "you" or "me." Some suggest that this may be because pronouns are not distinct enough in meaning; for example, the word "me" can have different meanings depending on the speaker. However, American Sign Language (ASL) simplifies the use of pronouns by using finger pointing to indicate "you" or "me." Shield reasoned that if students with autism avoid using pronouns for the sake of clarity, then deaf children with autism should have no problem using pronouns.
However, Shield’s study, which involved 23 deaf children with autism who had been signing since birth, yielded different results. Even when they had to use longer or more complex finger-spelling for names, the deaf children with autism still preferred using specific names instead of pronouns, just like their hearing counterparts with autism. Similarly, when learning new signs, the deaf children with autism accurately copied the signs rather than mirroring them. This mirrors the behavior of hearing students with autism who often "echo" a speaker’s words instead of responding to them.
These findings in deaf children further support the idea that language difficulties in autism may be linked to perspective taking and other cognitive skills related to language itself, rather than speech processing or articulation. "Having rich and comprehensive exposure to language is not enough to acquire it; one must also possess the social skills to access it," explained Shield.